Wondering what they are? Swagbucks is a search engine. When you use it, you get Swag Bucks (points) to spend. There is a huge variety of prizes to choose from, but the best point for dollar value is a $5.00 Amazon gift certificate for 450.
You usually earn them in increments of around ten. I have found that I almost always get ten-ish in my second to third search of the day. I also seem to get them again later in the day, if I search again.
I will admit that it's not the best search engine, but I still love using it for the benefits! The main problem I have with it is the sponsored results are not separated from the "real" ones. If I really want to find something fast or more complicated, I use the drop down menu for my search engines and switch to Google. I use Swagbucks to get to the sites I normally go to. Instead of using a bookmark, I type in the name of the website, to potentially earn points. (I just type in a few letters and let it auto-fill the rest.) It's fairly simple and fast.
I figure I earn about $5.00 a month in Amazon gift cards by using it, without any referral bonuses. (If you refer people, you will earn more than that since they will give you matching Swag Bucks for the first 1000 they earn.) I figure it's something simple to do that will be $60+ in my pocket at the end of the year. You can order Amazon certificates at any time and have them accumulate in your Amazon account for larger purchases. (I believe there is a limit for redeeming for the same certificates each month, so don't let your points accumulate for too long if you're going for the "cheap" stuff.)
It's simple to sign up and you can always cancel and/or just not use it. You can get more specifics HERE.